It is a very very nice looking boat bell, they are obviously rare and pricey when from a serving vessel.
I'd love to hear it's ring.
Wonder how Charles acquired it? RN submarine museum perhaps?
We have a submarine base bell, 9", from the 1950's, that has a lovely chime; I rigged it up as our doorbell in our previous house.
But damn, I'd love to be gifted a proper ships bell!